This invention relates to rocket motors and particularly to the use of rocket motor bleed gases for actuation of rocket control accessories. Based on the fact that the main rocket motor chamber can supply gas for actuation of thrust vector control means and thrust modulation control devices, for example, without impairing motor performance, a system which converts motor chamber gas to usable gas can eliminate a separate power source for this purpose.
The concept of conditioning motor bleed gases is fairly new and there are only a few designs using this concept. Of these designs, only a very few use a decomposing chemical to cool the gases and none of the known designs use a coolant as an aid to alumina filtration.
The consensus in the trade has been that aluminum oxide in hot gases can be easily filtered without cooling. However, this has not been found to be the case because, at elevated temperatures, the aluminum or its compounds are liquid and very difficult or impossible to remove by filtration.
According to the present invention, a filter cooler is provided which considerably lowers the temperature of the hot gases before filtering so that alumina in the gases is more easily and efficiently removed.